When the Window Is Already Missed

Part of Clinical Laboratory (LAB) Training: Stability, Timing and the Clock.

About 2 minutes. Free, in your language, no account needed.

It happens, and it is survivable

Couriers are late. Draws run behind. A centrifuge fails. Windows get missed in every study that has ever run.

What separates a manageable event from a serious one is what you do in the next ten minutes.

Establish the facts before you decide

Actual collection time. Actual receipt time. Actual current time. Storage conditions in between, if you know them.

Write them down before you do anything else. Once you start processing, some of these become harder to reconstruct.

Do not discard the sample

The decision to exclude a sample belongs to the sponsor, not to the bench.

A sample that is outside its window may still be usable for some analytes and not others. It may support a secondary endpoint. The sponsor holds that judgment because they know what the data is for.

Process and store it according to the manual, label the deviation clearly, and let them decide.

Report it the same day

A deviation reported promptly is an event with a known cause and a documented response.

The same deviation surfaced by a monitor three months later is a finding, and it raises the question of what else went unreported.

The content of the problem does not change. The interpretation of your laboratory does.

Say what you do not know

If the sample sat in reception for an unknown period, say so. "Receipt time not recorded by reception; sample found at 14:20" is a usable, honest record.

Inventing a plausible time to close the gap is the worst available option. It converts an operational problem into a data integrity problem.

Look for the pattern

One missed window is an event. Three in a month from the same site is a systemic issue with a fixable cause, usually courier scheduling or draw timing.

Reporting each one individually is what makes the pattern visible. Handling them quietly at the bench is what hides it until it has affected a hundred samples.